This work describes the influence of coherent illumination on phase measurement accuracy in digital holographic microscopy (DHM). To improve net phase accuracy in a DHM system, the phase referencing and temporal averaging techniques are applied simultaneously to suppress the phase noises caused by the laser source and image sensor. A comparison between a laser diode operated in single- and multi-modes is given to demonstrate the coherence effect on the fringe visibility and the reconstructed phase accuracy of digital holograms. Axial sub-nanometer accuracy in DHM with the fewest successive hologram recordings is performed using a wavelength-stabilized laser diode in single-mode operation.
- digital holography
- laser diodes
- phase measurement
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics